IRIS 3000



The IRIS 3000 systems were the last Motorola based machines SGI ever produced. They have been replaced by the MIPS based 4D series workstations.

The basic bus system for the IRIS 3000 architecture is still Multibus, but for the interconnection between CPU, FPU and memory a private bus is used which was also present on the IRIS 2000 Turbo models.

The IRIS 3000 was the last SGI system that used a Motorola 680x0 CPU. It was superseded by the IRIS 4D line which is based on MIPS RISC microprocessors. The first system of that new line is the Professional Iris.


The following table includes a list of the models of the IRIS 3000 line.

Model Type CPU Graphics Disk Chassis
IRIS 3010 Terminal IP2 Enhanced IRIS Graphics (10 GE, 8 Bitplanes) ST-506 (20MB) unknown
IRIS 3020 Workstation IP2 Enhanced IRIS Graphics (10 GE, 8 Bitplanes)

ST-506 (76MB)

IRIS 3030 Workstation IP2 Enhanced IRIS Graphics (10 GE, 32 Bitplanes) ESDI (170MB) unknown
IRIS 3110 Workstation IP2 Enhanced IRIS Graphics (10 GE, 8 Bitplanes) ST-506 20-slot
IRIS 3115 Workstation IP2 Enhanced IRIS Graphics (12 GE, 8 Bitplanes) ST-506 20-slot
IRIS 3120 Workstation IP2 Enhanced IRIS Graphics (12 GE, 8 Bitplanes) ESDI 20-slot
IRIS 3130 Workstation IP2 Enhanced IRIS Graphics (12 GE, 32 Bitplanes) ESDI 20-slot


1986, February
The IRIS 3000 product line is introduced featuring 3 models: 3010 teminal, 3020 workstation and 3030 workstation.
1989, November
SGI is positioning the IRIS 3100/3000 products as "mature" and formalizing the end of production for the IRIS 2000 series products. Support (including availability of parts) is guaranteed for at least 5 years until October 1994.



All IRIS 3000 systems are equipped with the IP2 processor board ("Inhouse Processor 2") which was also used in the IRIS 2000 Turbo models.

The following table includes the characteristics of the IP2 processor board:

CPU Board Procesor Clockspeed
IP2 Motorola 68020 16 MHz


IM1 Memory

IM1 memory.

IRIS 3000 systems need an IM1 memory board. It connected to the private bus connection initiated by the IP2 CPU board. Thus bus is separate from the Multibus backplane.

Using IM1 boards the memory can be upgraded from 2 to 16 MB on IRIS 3000 workstations and from 2 to 12 MB on IRIS 3000 terminals. The IM1 board is available in 2 MB and 4 MB versions.

As the single RAM chips are hardwired to the IM1 board a memory upgrade requires replacement or addition of IM1 boards. Note that the last one in a chain of memory boards needs to be terminated using an IM1 terminator.

The IM1 memory board is also used with the IRIS 2000 Turbo models. It is not compatible with IRIS 2000 non-Turbo models.


The Enhanced IRIS graphics featuring 10x 8 MHz Geometry Engines is used in IRIS 3010, 3020 and 3030 systems.

The later IRIS 3110, 3115, 3120 and 3130 models include the top of the line IRIS graphics option featuring 12x 10 MHz Geometry Engines.


Upgrading the IRIS 3000 systems most likely requires adding further boards to the cardcage of the system.

Some of the IRIS 3000 systems shipped have been crippled to allow only a ristricted number of option cards. This has been obvious in examples where no further slots were available to add more than one IM1 memory board.

The backplane may not have the appropriate connectors on the backplane in such cases and the chassis will not have the guiding rails in which the boards are inserted.


Excelan ethernet.

  • IBM 3270 Coax Link
  • Intelligent 8-Port Serial I/O Controller
  • Excelan EXOS/201 Ethernet board
  • Qualogy DSD 5217 ST-506/QIC-02
  • Interphase Storager II STO-506/QIC-02/ESDI
  • Interphase 2190 SMD
  • CG1 Genlock option for IRIS 2000/3000
  • Peripherals: Dials and Buttons



width:     45,7 cm / 18"
height:    73,6 cm / 29"
depth:     68,6 cm / 27"

weight:    90,7 kg / 200 lbs


Control Data

IRIS 3000 systems were also sold by Control Data Corporation under their own label. At least relabelled IRIS 3130 models do exist, possibly other configurations were sold as well by Control Data.


Operating System

Choosing an operating system.

The IRIS systems run the GL2 operating system which predates IRIX. The IRIS 3000 models are supported by GL2 Release 3.

DIP Switches

What is the meaning of the DIP Switches?

The following is an explanation of the workstations DIP switches (0 open / 1 closed):

Switch Name Setting Meaning
1-4 Boot Environment 1111
Hard disk boot
Cartridge tape boot
Floppy disk boot
Network boot
PROM monitor
5 Autoboot 1
PROM Monitor boot
Automatic boot
6 Quiet Mode


Display system Information
Don't display system Information
7 Monitor Select 1
Display on primary monitor
Display on secondary monitor
8-9 Reserved 1  



IRIS 3130

Front of an IRIS 3130 system.

Front of an IRIS 3130 system.

Front of an IRIS 3130 system with cover taken off.

IRIS 3130 with cardcage opened.

Closeup of the IRIS 3130 cardcage.

Back of an IRIS 3130.

CPU and Memory


FP1 floating point unit.

IM1 memory.

IM1 terminator.


GF2 board.

BP3 board.

BP3 board.

BP3 board.

DC4 board.

UC4 board


Excelan ethernet.

Storager option.




  • - a video that includes a presentation of an IRIS computer (from ~1984).